S drives his car and covers 37 km and 500 m in 90 minutes. What is his average speed (in km/h)?

The correct option is 25.

To find the average speed of the car in km/h, we convert the total distance into kilometers and the total time into hours, and then apply the speed formula.

Step 1: Convert distance into kilometers (km)

The total distance covered is 37 km and 500 m.

Since 1 km = 1000 m, we convert 500 m into kilometers:

$500\text{m}=\frac{500}{1000}\text{km}=0.5\text{km}$

Now, add this to 37 km to get the total distance:

$\text{Total Distance}=37\text{km}+0.5\text{km}=37.5\text{km}$

Step 2: Convert time into hours (h)

The total time taken is 90 minutes.

Since 1 hour = 60 minutes, we convert 90 minutes into hours:

$\text{Total Time}=\frac{90}{60}\text{hours}=1.5\text{hours}$

Step 3: Calculate the average speed

The formula for average speed is:

$\text{Average Speed}=\frac{\text{Total Distance}}{\text{Total Time}}$

Substituting the values of distance and time into the formula:

$\text{Average Speed}=\frac{37.5\text{km}}{1.5\text{h}}=25\text{km/h}$

Thus, S's average speed is 25 km/h.